VF said
If a CodeCanyon author receives item comments, it shows on dashboard only when the dashboard page opened through CodeCanyon. If the author doesn’t have item on TF, then the dashboard doesn’t show unread comments through TF dashboard. This is actually an unnecessary change; hope this is possible to fix in no time.

That feels like a bug we’ve introduced accidentally at some point, rather than a deliberate design decision. In fact, that’s the opposite of where I want to head with that page. I’ve filed a ticket.